diff --git a/canaille/templates/oidc/admin/authorization_view.html b/canaille/templates/oidc/admin/authorization_view.html
index 9ed6cbba..8798e3cd 100644
--- a/canaille/templates/oidc/admin/authorization_view.html
+++ b/canaille/templates/oidc/admin/authorization_view.html
@@ -39,7 +39,7 @@
         <div class="ui attached clearing segment">
             <ul>
                 {% for attr in authorization.attributes %}
-                    <li>{{ attr }}: {{ authorization[attr] }}</li>
+                    <li>{{ attr }}: {{ authorization[attr]|string }}</li>
                 {% endfor %}
             </ul>
         </div>